Brain stereotactic radiosurgery
Overview
Overview
Brain stereotactic radiosurgery (SRS) is a radiation treatment for specific brain conditions. It works by delivering highly focused beams of energy to defined areas in the brain. It's not surgery in the traditional sense — it involves no cuts or openings in the skull. But the radiation is delivered with virtually the same precision as a surgical tool.
Doctors use detailed pictures of the brain along with special computer software to map the treatment area and guide the radiation. Each beam alone delivers a small dose of radiation. But where the beams meet, they deliver a concentrated dose that destroys the target cells while sparing surrounding tissues. This precision lessens side effects. And it allows many people to go back to their usual activities shortly after treatment.
Radiation works by damaging the DNA of the targeted cells. DNA is like a cell's instruction manual. When the DNA is damaged, the cells can't function or multiply, and they eventually die. These effects may take some time, but the treatment can be very effective.
Brain SRS can treat:
Several types of technology are used to deliver radiation during brain SRS. The main difference between them is that their energy comes from different sources.
Why it's done
Why it's done
Brain SRS may be used to treat the following conditions:
Brain SRS may be chosen over traditional brain surgery because it avoids risks of open surgery, such as bleeding, infection and nerve damage.
Brain SRS may be recommended when:
Risks
Risks
Brain SRS is generally safe and effective. Like any medical procedure, it carries risks of side effects. Some arise soon after treatment; others may be delayed.
Early side effects may include:
Delayed side effects are rare. They may include:
How you prepare
How you prepare
Wear comfortable, loose clothing.
Avoid wearing the following items during the procedure:
Tell a member of your healthcare team if you:
What you can expect
What you can expect
Careful planning is required to deliver radiation to exactly the place in your brain that needs treatment. Two things need to happen: Your head needs to stay still while the treatment area is mapped out. And your head needs to be in the exact same position relative to radiation beams on the day of treatment. To get ready, you go through a planning session called simulation.
To help keep your head firmly in place, your healthcare team may use a fixed head frame or a custom mask. This frame or mask also serves as a point of reference for focusing the beams of radiation.
You use the same frame or mask every time you have a treatment.
Your SRS team conducts imaging tests to pinpoint the location of the treatment area in relation to the frame or mask.
The images are entered into a computer to plan exactly how much radiation to deliver and from what angles. This planning process usually takes less than an hour.
During that time, you can relax in another room. The frame, if it is used, must remain attached to your head. If a mask is used instead of a frame, some of the planning takes place before the mask is placed.
Children often get medicines to put them in a sleeplike state for the simulation and the procedure. Adults are usually awake but may be given a medicine to help them relax.
If a head frame is used, the frame is attached to your head. The head frame attaches securely to a docking device on the table you lie on.
If a custom mask is used, you may lie on a specialized neck support and a healthcare professional puts the mask on your face.
The machine may rotate around you, move on robotic arms or slide you into a treatment unit depending on the system used.
You get fluids directly into your bloodstream through an intravenous (IV) line. The fluids keep you hydrated during the procedure.
It can take up to four hours to complete the procedure. The time depends on the size and shape of the target. During the procedure:
Brain SRS usually is an outpatient procedure, which means you probably won't have to stay overnight in the hospital. But the entire process may take most of the day. You may be asked to bring a family member or friend who can be with you during the day and who can take you home. Rarely, you may stay overnight in the hospital.
After the procedure:
An advantage of brain SRS over some other types of treatment, such as traditional brain surgery, is that recovery is short and major side effects are not common. Most people can go back to their usual activities within a day or two after the procedure.
Small tumors are often treated in a single session. Larger tumors or those near important brain areas may require 3 to 5 sessions. Recovery time varies depending on the condition treated and individual response.
Results
Results
The effects of brain SRS happen gradually depending on the condition being treated:
Your healthcare team may schedule follow-up exams to monitor your progress.
Updated on Sep 26, 2025
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